March 11, 2009 (San Diego, California) — Oxygen/ozone injections into herniated lumbar discs are equal in efficacy to surgical discectomy in the areas of pain relief and function outcome, but the complication rate is considerably lower and the recovery time is significantly shorter, according to a new meta-analysis presented here at the Society of Interventional Radiology 34th Annual Scientific Meeting.
The therapy involves an interventional radiologist using computer imaging to guide a needle that injects a gas mixture of oxygen and ozone directly into the injured lumbar disc. The procedure is a minimally invasive radiologic treatment that is expected to become a standard option for patients within the next couple of years, according to researchers. Currently, open discectomy and microdiscectomy are the standard in surgical treatments; they both involve removal of disc material through an incision.
Ozone Is a Sterilizing Agent
|Dr. Kieran J. Murphy|
"Undergoing invasive surgical discectomy puts you on a path where you may be left with too little disc, but this procedure will lower the number of patients who require surgery because the oxygen/ozone will result in the patient's body being able to shrink and heal their disc," investigator and presenter Kieran J. Murphy, MD, interventional neuroradiologist and vice chair and chief of medical imaging at the University of Toronto, in Ontario, said during a news conference.
"Ozone is a sterilizing agent with no infection associated with it — it is used in hospitals to sterilize equipment; they'll bring an ozonator to your hotel room to clean the air if you complain about smoke," he added.
Dr. Murphy said he learned the process in Naples, Italy, working with Mario Muto, MD, and colleagues at Cardarelli Hospital, where he personally did a few of the herniated disc treatments. He said the oxygen/ozone therapy is de rigueur in Italy. From June 2000 to December 2006, the Muto group performed the oxygen/ozone procedure on 2900 patients with lumbar disc herniation.
Dr. Murphy told Medscape Radiology that the oxygen/ozone mixture injected into the disc works through a redox (or reduction–oxidation) reaction. This is a chemical reaction in which atoms have their oxidation state changed. "It is the biochemical properties of the oxygen and ozone that interact with proteoglycan's core protein that is broken into smaller portions, shrinking disc volume, which in turn relieves the pain," he said.
Treatment outcomes for the oxygen/ozone treatment of herniated discs were estimated using a random-effects meta-analysis. Researchers conducted a literature search that used search terms associated with ozone treatment for herniated discs, and weighted each study with a study-quality score. Separate meta-analyses were performed for visual analog scale (VAS), Oswestry Disability Index (ODI), and Modified MacNab scale scores; a meta-analysis for the overall complication rate also performed.
Of 24 articles, 13 (comprising more than 8000 patients from multiple hospital centers) met the inclusion criteria.
"The overall estimated mean improvement was 3.9 for VAS and 25.5 for ODI. The estimated chance of showing improvement in the Modified MacNab scale was 79.7%. The estimated chance of complications was 0.003%," according to the study abstract.
Dr. Murphy, who is on deck to be program chair for next year's SIR annual meeting, said that, "based on these results, we're working on a clinical-trial design involving 50 patients and should hear from the [US Food and Drug Administration] within the next 18 months to 2 years. When you have 79.7% of patients with a herniated disc getting improvement from this procedure, that's pretty cool."
Scientifically, It Makes Sense
Brian Stainken, MD, interventional radiologist at Roger Williams Medical Center, in Providence, Rhode Island, and moderator of the session at which the meta-analysis was presented, said that minimally invasive solutions targeted to problem areas are needed. "Dr. Murphy may have one of these solutions here."
Dr. Stainken told Medscape Radiology that he thought the ozone procedure could be an option for those who suffer from back pain. "Scientifically, it makes sense — and now what they need to do is to validate this technique with additional research and then work on delivering that solution to our patients."
He added: "It's the job of the interventional radiologist to figure out what works and then to deliver it, to know which tools are best used and when to use them."
Dr. Murphy invented a device to perform the oxygen/ozone procedure and has formed a company. Dr. Stainken has disclosed no relevant financial relationships.
Society of Interventional Radiology (SIR) 34th Annual Scientific Meeting: Abstract 37. Presented March 9, 2009.
Medscape Medical News © 2009 Medscape
Cite this: Kristina Rebelo . SIR 2009: Oxygen/Ozone as Effective as Discectomy for Herniated Disc Pain - Medscape - Mar 11, 2009.